Los Angeles police say Lee Thompson Young, 29, was found dead Monday morning, Aug. 19, 2013. The actor started his career as a teenager in the TV series "The Famous Jett Jackson" and was co-starring in the TNT series "Rizzoli & Isles."Darren Michaels / TNT

Former Disney Channel star Lee Thompson Young died of a self-inflicted gunshot wound and was taking drugs to treat depression but had no illicit substances in his body at the time of his death, an autopsy report released Tuesday by the Los Angeles County coroner found.

Young, best known for playing the title character on the Disney Channel show “The Famous Jett Jackson,” died at his North Hollywood apartment of a gunshot to the right temple.

At the time of his death, Young had a history “of bi-polar disorder and depression” and was taking lithium and quetiapine fumarate, the coroner’s report states. Toxicology tests found no sign of illicit drugs.

The 29-year-old actor was last heard from August 17th at 2:30 p.m. when he had a conversation with a friend. When he failed to show up for work at a movie set, friends requested authorities to make a “welfare check.” Young was found next to a couch on the 19th.

A witness who was not identified in the report denied to coroner’s officials that he had made any previous suicide threats or attempts, and said she was unaware of any financial problems.

The weapon used in the suicide was described in the report as 40 caliber Sig Sauer semi-automatic handgun and was registered to Young. There were nine rounds left in the gun and one spent shell recovered from the bottom cushion of the couch.

The South Carolina native is best known for the title role in the Disney Channel series "The Famous Jett Jackson." He also appeared in the ABC drama "Flash Forward" and the movie "Friday Night Lights."

In 2010, Young was cast as Detective Barry Frost on the TNT police drama "Rizzoli & Isles.”

At the time of his death, Young’s manager Jonathan Baruch released a statement to the entertainment site “Deadline” calling his client “more than just a brilliant young actor ... a wonderful and gentle soul.”